Machines for reading and sorting paper documents are used in a variety of applications. One such application is in the banking industry in which encoded documents, such as checks and bank deposit slips, are processed by a high-speed reader sorter machine in which the documents are read, sorted (e.g., by bank routing or account numbers) and then stacked in appropriate pockets in the sequences in which the documents enter the corresponding pockets. During high-speed operation, paper jams and foldovers in the pockets may occur because of differing sizes, thicknesses and weights among the documents being received in the pockets. A common cause of paper jams in the pockets is a collision between the leading edge of an incoming document and the trailing edge of a previously pocketed document.